Optimize hot-path utility helpers for string escape and object filtering

.gitignore

@@ -57,6 +57,7 @@ build/Release
 # Dependency directories
 
 node_modules/
+package-lock.json
 jspm_packages/
 
 # Snowpack dependency directory (https://snowpack.dev/)

packages/lib/src/utils/object/modify.test.ts

@@ -8,4 +8,9 @@ describe('Modifying objects', () => {
   test('pick keys', () => {
     expect(pick({ a: 1, b: 2 }, ['a'])).toEqual({ a: 1 })
   })
+
+  test('handles duplicate keys', () => {
+    expect(pick({ a: 1, b: 2 }, ['a', 'a'])).toEqual({ a: 1 })
+    expect(exclude({ a: 1, b: 2 }, ['a', 'a'])).toEqual({ b: 2 })
+  })
 })

packages/lib/src/utils/object/modify.ts

@@ -3,8 +3,9 @@ export function pick<T extends any, K extends (keyof T)[] = []>(
   keys: K
 ): Pick<T, K[number]>
 export function pick(object: any, keys: string[]) {
+  const keySet = new Set(keys)
   return Object.fromEntries(
-    Object.entries(object).filter(([key]) => keys.includes(key))
+    Object.entries(object).filter(([key]) => keySet.has(key))
   )
 }
 
@@ -14,8 +15,9 @@ type ExcludeFunction = <T extends object, K extends (keyof T)[] = []>(
 ) => Omit<T, K[number]>
 
 export const exclude: ExcludeFunction = (object, keys: any): any => {
+  const keySet = new Set(keys)
   return Object.fromEntries(
-    Object.entries(object).filter(([key]) => !keys.includes(key))
+    Object.entries(object).filter(([key]) => !keySet.has(key))
   )
 }
 

packages/lib/src/utils/string/normalize.ts

@@ -1,5 +1,28 @@
 import { pipe } from '../function/pipe'
 
+const ESCAPE_MAP: Record<string, string> = {
+  '&': '&amp;',
+  '<': '&lt;',
+  '>': '&gt;',
+  '"': '&quot;',
+  "'": '&#39;'
+}
+const UNESCAPE_MAP: Record<string, string> = {
+  '&amp;': '&',
+  '&lt;': '<',
+  '&gt;': '>',
+  '&quot;': '"',
+  '&#39;': "'"
+}
+const ESCAPE_REGEX = new RegExp(
+  `(${Object.keys(ESCAPE_MAP).join('|')})`,
+  'g'
+)
+const UNESCAPE_REGEX = new RegExp(
+  `(${Object.keys(UNESCAPE_MAP).join('|')})`,
+  'g'
+)
+
 // TODO: refactor
 
 export function normalizeNewLines(string_: string) {
@@ -39,35 +62,15 @@ export function normalizeNewLines(string_: string) {
 }
 
 export function escapeHtml(unsafeText: string): string {
-  const map: Record<string, string> = {
-    '&': '&amp;',
-    '<': '&lt;',
-    '>': '&gt;',
-    '"': '&quot;',
-    "'": '&#39;'
-  }
-
   return pipe(
-    Object.keys(map),
-    (keys) => keys.join('|'),
-    (match) => new RegExp(`(${match})`, 'g'),
-    (regex) => unsafeText.replaceAll(regex, (match) => map[match])
+    unsafeText,
+    (text) => text.replaceAll(ESCAPE_REGEX, (match) => ESCAPE_MAP[match])
   )
 }
 
 export function unescapeHtml(unsafeText: string): string {
-  const map: Record<string, string> = {
-    '&amp;': '&',
-    '&lt;': '<',
-    '&gt;': '>',
-    '&quot;': '"',
-    '&#39;': "'"
-  }
-
   return pipe(
-    Object.keys(map),
-    (keys) => keys.join('|'),
-    (match) => new RegExp(`(${match})`, 'g'),
-    (regex) => unsafeText.replaceAll(regex, (match) => map[match])
+    unsafeText,
+    (text) => text.replaceAll(UNESCAPE_REGEX, (match) => UNESCAPE_MAP[match])
   )
 }